1. Field of the Invention
The present invention relates generally to electromagnetic energy emitting devices and, more particularly, to pulsed medical treatment laser devices.
2. Description of Related Art
A variety of electromagnetic laser energy generating architectures have existed in the prior art. A solid-state laser system, for example, generally comprises a laser rod for emitting coherent light and a source for stimulating the laser rod to emit the coherent light. Flashlamps are typically used as stimulation sources for middle infrared lasers between 2.5 microns (μm) and 3.5 μm, such as Er,Cr:YSGG and Er:YAG laser systems. The flashlamp is driven by a flashlamp current, which comprises a predetermined pulse shape and a predetermined frequency.
The flashlamp current drives the flashlamp at the predetermined frequency, to thereby produce an output flashlamp light distribution having substantially the same frequency as the flashlamp current. This output flashlamp light distribution from the flashlamp drives the laser rod to produce coherent light at substantially the same predetermined frequency as the flashlamp current.
Medical applications, such as those requiring the excision of soft human tissue, may in some instances require or benefit from two opposite tissue effects. The first effect may relate to laser cutting of tissue with controlled hemostasis, minimal to no bleeding, and attenuated or eliminated charring of cut surfaces. The second effect may relate to laser cutting with bleeding in order, for example, to stimulate post-operative healing when tissue is brought together. The second effect can be particularly important or relevant, for example, in grafting applications.
Prior art methods of generating these first and second effects can include employing distinctly different devices for each type of tissue cutting. Some prior art methods of performing first and second effect procedures may include employing systems capable of generating different wavelengths of laser energy. For example, wavelengths of about 1 μm and about 3 μm may be generated using CO2 and Erbium type lasers, respectively. Overhead time and effort that may be required in switching between two medical devices can be disadvantages of this approach. Extra time and attendant discomfort from a point of view of a patient undergoing such procedures may represent additional disadvantages.
A need exists in the prior art for laser devices capable of rapidly and efficiently transitioning between varying characteristics or modes of operation, to facilitate, for example, different desired cutting effects or procedures such as for facilitating both hemostatic-type and bleeding-type tissue cutting effects